Link D P, Strandberg J D, Virmani R, Blashka K, Mourtada F, Samphilipo M A
Department of Radiology, University of California Davis Medical Center, Sacramento 95817, USA.
J Vasc Interv Radiol. 1996 Nov-Dec;7(6):897-905. doi: 10.1016/s1051-0443(96)70868-0.
This study observes the histologic changes resulting from a hydrogel embolic agent (polyacrylonitrile [PAN]) compared with polyvinyl alcohol particles (PVA) of similar size.
Hepatic and renal embolizations were performed in 13 domestic swine by selecting small (1-mm) branches utilizing a coaxial 3-F microcatheter. The hydrogel embolic agent (tantalum-loaded and plain) and PVA were delivered through microcatheters. The longest follow-up period was 8 weeks. Postmortem examination of the embolized tissues included gross examination and histologic analysis.
Tantalum-loaded PAN particles were radiopaque and seen in groups fluoroscopically and individually with specimen radiography. Histologic studies showed similar luminal and cellular response to PVA and the hydrogel embolic agents. The arterial lesion induced by the hydrogel embolic agents led to an absence of the arterial wall locally in the area of deployment. Hydrogel embolic particles became surrounded in fibrous connective tissue with no arterial wall. PVA and porous hydrogel capsules produced an inflammatory response, resulting in less wall reorganization, and surrounding fibrous connective tissue at 8 weeks than the solid PAN particles.
These hydrogel embolic create a permanent arterial occlusion by transmural arterial damage. Mechanical effects and, to a lesser degree, inflammatory changes are responsible.
本研究观察与大小相似的聚乙烯醇颗粒（PVA）相比，水凝胶栓塞剂（聚丙烯腈[PAN]）所导致的组织学变化。
通过使用同轴3F微导管选择小的（1毫米）分支，对13头家猪进行肝和肾栓塞。水凝胶栓塞剂（含钽和普通型）和PVA通过微导管输送。最长随访期为8周。对栓塞组织进行尸检，包括大体检查和组织学分析。
含钽的PAN颗粒在荧光镜下可见为不透射线的，在标本射线照相中可单个看到。组织学研究显示，PVA和水凝胶栓塞剂的管腔和细胞反应相似。水凝胶栓塞剂引起的动脉病变导致在部署区域局部动脉壁缺失。水凝胶栓塞颗粒被无动脉壁的纤维结缔组织包围。与实心PAN颗粒相比，PVA和多孔水凝胶胶囊产生炎症反应，在8周时导致更少的管壁重塑和周围纤维结缔组织。
这些水凝胶栓塞剂通过透壁动脉损伤造成永久性动脉闭塞。其原因是机械效应以及程度较轻的炎症变化。
